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1.
1INTRODUCTIONJianghanPlainisoneoftheimportantbasesofChina′sagriculturalproductivitylocatedinthemiddleChangjiangRivervalleyofcentralChina.TheJianghanplainapproximately6.6×104km2inareaandover30millioninpopulationistherenowned“countryoffishandrice"in…  相似文献   

2.
近30年天津滨海新区湿地景观格局遥感监测分析   总被引:6,自引:0,他引:6  
在GIS和FRAGSTATS软件支持下,结合景观格局数量分析方法,利用1979-2008年间共6期TM遥感影像与非遥感数据,对天津滨海新区近30年的湿地景观空间格局进行了动态分析。结果表明,滨海新区湿地(以人工湿地为主),1979-2004年滨海新区湿地总面积变化不大,但各类型间转换较大,主要是自然湿地转变为人工湿地,沼泽湿地几近消失。2006-2008年,由于城市建设大量滨海滩涂湿地被围填占用,到2009年5月自然海岸线的90%以上被占用。景观破碎度增加,湿地斑块数量从137个增加到704个,同时造成平均斑块面积下降。驱动力分析表明,降雨量减少的同时,年平均气温上升是主要的自然驱动因素。和自然因素相比,人类干扰为主要人文驱动因素,表现在水产养殖为主的农业经济活动、城市建设用地占用和围海造地等方面。目前,滨海新区几乎没有自然湿地生态系统,破碎化和人工化是该区域湿地的主要特征。  相似文献   

3.
湿地是水陆交错的生态系统,往往受旱灾影响大,故此,对不同湖泊湿地受旱程度差异及其原因分析,可为减灾和湿地保护提供科学依据。本文利用2010年5月和2011年5月2个时相的HJ-1卫星CCD影像,提取洪湖和梁子湖2个时相的湿地水面积,结合统计资料和问卷调查数据,从湿地水面积及空间分布变化、湿地生态系统功能退化、湿地生态系统,对人类福祉影响3方面,分析了两湖湿地受旱程度的差异。并综合气象数据、统计资料和问卷调查数据,从气象因子、区域自然地理环境、湿地类型及特点、区域水文条件和湿地受保护程度5方面探讨两湖受旱程度差异的原因。结果表明:(1)2011年春旱期间,洪湖比梁子湖受旱程度更严重。旱灾时,洪湖水面积减少83.93 km2,减小比例为26%,梁子湖水面积减少13.02 km2,减小比例为4%;两湖的涵养水源、保护生物多样性、物质生产和水质净化功能均受到损害,洪湖较梁子湖更严重;受旱灾影响,洪湖湿地对人类福祉的消极影响大于梁子湖。(2)降雨量、气温和风速等气象因素、湖泊湿地成因类型、区域自然地理环境和水文条件是影响两湖受旱程度差异的主要因素,另外,湿地保护措施的差异及效果也会造成两湖受旱程度不同。  相似文献   

4.
STUDY ON WETLAND LOSS AND ITS REASONS IN CHINA   总被引:2,自引:2,他引:0  
1INTRODUCTIONWetlandsaretheecosystemswithmanyfunctionsandhavebeenprovidinguswitharangeoffunctionsandbenefitssuchaswatersupplyflowregulationsendimentretentionmoderationofclimatepreventionofsalinewaterintrusionetc.Althoughwetlandoccupyonlyabout6%…  相似文献   

5.
1 INTRODUCTION The Ussuri / Wusuli River watershed is located in the southeast part of Heilongjiang Province of China, which joins remote regions of Russia. The watershed consists of approximately 26 000 000 ha, which is about two thirds of the watershed ecosystem in Russia, one  third in China. The Ussuri River forms part of the border between Russia and China, the shared border stretches more than 1100 km. Khanka/Xingkai Lake lies within both China and Russia. Its total area …  相似文献   

6.
为开展江汉平原浅层地下水防污性能评价,以江汉平原沙洋-旧口地区浅层地下水为研究对象,针对传统DRASTIC模型评价指标存在关联性、权重主观性强、评分值缺乏连续性以及评价结果缺乏实测数据验证等缺点,考虑研究区实际条件,建立了基于改进DRASTIC模型的模糊综合评价模型,并利用研究区浅层地下水关键污染因子Cl-、NO3-和NH4+实测数据验证了模型的准确性和可靠性。该模型使用包气带黏性土厚度代替包气带介质指标,含水层厚度代替含水层介质指标、土壤饱和渗透系数代替土壤介质指标,采用全定量评价指标体系,评价指标更加客观、合理;采用三标度层次分析方法确定各评价指标权重,减少了传统DRASTIC模型人为确定权重的主观性;在改进的DRASTIC模型基础上,引入模糊数学理论,以隶属度函数代替传统DRASTIC模型固定评分值,克服了传统DRASTIC模型使用定额评分带来的不连续性。模糊综合评价结果表明:研究区浅层地下水防污性能整体表现为差-较差,占研究区总面积的76.53%。研究结果可为平原地区开展浅层地下水脆弱性评价提供方法参考,为江汉平原浅层地下水污染防治工作提供科学依据。   相似文献   

7.
Northeast China is the region with the largest area of wetlands in China. The Sanjiang Plain and the Songnen Plain are large freshwater marsh distribution regions that are affected by climate warming and by the increasing frequency and density of extreme weather and are the regions most subject to disturbances by human activities in Northeast China. The wetlands of the Sanjiang Plain and the Songnen Plain have shrunk severely in the past 60 years, and wetland functions have been reduced substantially because of climate change, unreasonable land use, fire episodes, engineering and construction works and urbanization. Large-scale agricultural development started in the 1950s has been the most important driving factor for wetland loss and degradation in the Sanjiang Plain. Water shortage has been the most important factor for degradation and fragmentation of wetlands in the Songnen Plain. To mitigate wetland degradation and better protect wetlands, special regulations, long-term mechanisms and technical support of wetland protection should be established. A wetland compensation program should be implemented, and technologies for increasing the adaptive capacity of wetlands should be developed. Moreover, it is most important to find the balanced threshold between agricultural development and wetland protection.  相似文献   

8.
溶解性有机碳(DOC)是地下水中砷释放过程的关键因素,为查明江汉平原高砷地下水稳定碳同位素特征,识别有机质的降解过程对砷富集的影响,采用稳定碳同位素分析测试技术并结合地下水化学特征,对江汉平原典型砷中毒病区的浅层地下水进行了区域采样分析。结果表明:浅层承压水的砷质量浓度为0.23~2 621 μg/L。地表水较地下水具有更负的δ13CDOC、δ13CDIC值。地下水中溶解性无机碳(DIC)的δ13CDIC值在-11.9‰~-3.99‰之间,溶解性有机碳的δ13CDOC值在-28.5‰~-19.6‰之间。地下水的δ13CDIC-δ13CDOC差值与ρ(As)呈一定负相关关系,表明微生物作用下有机质的降解促进了As的富集。δ13CDIC-δ13CDOC差值与δ13CDIC和ρ(DOC)均具有较显著的正相关关系,表明地下水中有机质的氧化分解是导致δ13CDIC贫化的重要过程,微生物作用下溶解性有机质的降解是地下水中无机碳的重要来源。此外,江汉平原少数高砷地下水呈现较大的δ13CDIC值,推断江汉平原高砷含水层强还原环境下可能存在的产甲烷过程导致了明显的碳同位素分馏。   相似文献   

9.
Soil organic matter(SOM) is an important parameter related to soil nutrient and miscellaneous ecosystem services. This paper attempts to improve the performance of traditional partial least square regression(PLSR) model by considering the spatial autocorrelation and soil forming factors. Surface soil samples(n = 180) were collected from Honghu City located in the middle of Jianghan Plain, China. The visible and near infrared(VNIR) spectra and six environmental factors(elevation, land use types, roughness, relief amplitude, enhanced vegetation index, and land surface water index) were used as the auxiliary variables to construct the multiple linear regression(MLR), PLSR and geographically weighted regression(GWR) models. Results showed that: 1) the VNIR spectra can increase about 39.62% prediction accuracy than the environmental factors in predicting SOM; 2) the comprehensive variables of VNIR spectra and the environmental factors can improve about 5.78% and 44.90% relative to soil spectral models and soil environmental models, respectively; 3) the spatial model(GWR) can improve about 3.28% accuracy than MLR and PLSR. Our results suggest that the combination of spectral reflectance and the environmental variables can be used as the suitable auxiliary variables in predicting SOM, and GWR is a promising model for predicting soil properties.  相似文献   

10.
Honghu Lake, located in the southeast of Hubei Province, China, has suffered a severe disturbance during the past few decades. To restore the ecosystem, the Honghu Lake Wetland Protection and Restoration Demonstration Project (HLWPRDP) has been implemented since 2004. A back propagation (BP) artificial neural network (ANN) approach was applied to evaluatinig the ecosystem health of the Honghu Lake wetland. And the effectiveness of the HLWPRDP was also assessed by comparing the ecosystem health before and after the project. Particularly, 12 ecosystem health indices were used as evaluation parameters to establish a set of three-layer BP ANNs. The output is one layer of ecosystem health index. After training and testing the BP ANNs, an optimal model of BP ANNs was selected to assess the ecosystem health of the Honghu Lake wetland. The result indicates that four stages can be identified based on the change of the ecosystem health from 1990 to 2008 and the ecosystem health index ranges from morbidity before the implementation of HLWPRDP (in 2002) to middle health after the implementation of the HLWPRDP (in 2005). It demonstrates that the HLWPRDP is effective and the BP ANN could be used as a tool for the assessment of ecosystem health.  相似文献   

11.
1 RESEARCH BACKGROUND According to the modern wetland concept, inland saline alkaline wetland is a component of wetland. In the world, it is mainly distributed in inland plain, plateau and basin of the arid or semi arid areas where there are fragile ecosystems deteriorated environment and poor biological resources which result in backward economy and poverty. Therefore, the study on inland saline alkaline wetland is significant for improving environment and realizing sustainable d…  相似文献   

12.
1 THE NATURAL ENVIRONMENTAL CHARACTERISTICS The Sanjiang Plain is located in the northeast of Heilongjiang Province, China. Russia borders this region in the north and east. Its total area is 1.088×107ha. The area of plain occupies 61.21%of the total land area and that of hill and mountain amounts to 38.79%of the total land area. It is not only one of the most important regions with large area of fresh water wetlands and with varieties of rare migratory waterfowls, but a…  相似文献   

13.
基于加权Voronoi图的北京市湿地功能分区研究   总被引:1,自引:0,他引:1  
湿地功能分区是城市湿地生态系统健康恢复、管理改善,以及资源可持续利用的重要前提。本文以北京湿地为例,利用客观赋权的主成分分析法对湿地生态服务功能进行综合评价;并结合空间分析中的Voronoi图空间分区方法,通过利用牛顿-断裂点模型确定属性权重的主要步骤,构建基于加权Voronoi图的城市湿地功能分区模型,开展"自下而上"定量化的北京湿地功能分区研究。结果表明:(1)北京湿地功能综合评价中,密云水库湿地的功能综合值最大,表明该湿地生态服务功能作用最重要。(2)北京湿地功能分区分为三级框架,其中包括4个一级核心湿地功能区、15个二级核心湿地功能区、43个三级核心湿地单元。(3)湿地资源功能价值量与湿地斑块空间关系的相结合,实现了属性和空间双重距离约束的湿地功能分区,促进了湿地生态系统服务价值评估在决策管理中的深入应用,为城市湿地功能区划提供技术支持。  相似文献   

14.
Wetland research has become a hot spot linking multiple disciplines presently. Wetland classification and mapping is the basis for wetland research. It is difficult to generate wetland data sets using traditional methods because of the low accessibility of wetlands, hence remote sensing data have become one of the primary data sources in wetland research. This paper presents a case study conducted at the core area of Honghe National Nature Reserve in the Sanjiang Plain, Northeast China. In this study, three images generated by airship, from Thematic Mapper and from SPOT 5 were selected to produce wetland maps at three different wetland landscape levels. After assessing classification accuracies of the three maps, we compared the different wetland mapping results of 11 plant communities to the airship image, 6 plant ecotypes to the TM image and 9 landscape classifications to the SPOT 5 image. We discussed the different characteristics of the hierarchical ecosystem classifications based on the spatial scales of the different images. The results indicate that spatial scales of remote sensing data have an important link to the hierarchies of wetland plant ecosystems displayed on the wetland landscape maps. The richness of wetland landscape information derived from an image closely relates to its spatial resolution. This study can enrich the ecological classification methods and mapping techniques dealing with the spatial scales of different remote sensing images. With a better understanding of classification accuracies in mapping wetlands by using different scales of remote sensing data, we can make an appropriate approach for dealing with the scale issue of remote sensing images.  相似文献   

15.
The paper, taking Songliao Plain for example, studied the concept, distribution law and formation mechanism of inland saline-alkaline wetland. The inland saline-alkaline wetland is distributed over the inland region of arid or semi-arid climate; it is the wet or slightly stagnant environment, forming saline-alkaline soil and salt vegetation and making the geogra phical environment fonming complex with an ecosystem of saline-alkaline wetland. The laws of zone nature and non-zone nature control the distribution of the inland saline-alkaline wetland that extensively spreads in north part of China and other countries. The inland saline-alkaline wetland is formed jointly by atmosphere, hydrosphere, lithosphere and biosphere including intellectual sphere. Under the special condition, the artificial activity is possibly the key function. In order to improve the human environment, it is a great duty confronting the whole world to rationally transform the inland saline-alkaline wetland. Therefore, we presented an anti-inland theory to promote the environment transformation. Foundation item: Under the auspices of the project of the Chinese Academy of Sciences (KN95 — 02). Biography: SUN Guang-you(1940 — ), male, a native of Harbin, professor. His research interests include geography, wetland.  相似文献   

16.
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17.
WETLANDS IN CHINA: FEATURE, VALUE AND PROTECTION   总被引:2,自引:1,他引:1  
The estimated total area of wetland in China is more than 25.9 million hectares including about 11.9 million hectares of marshes and bogs, 9.1 million hectares of lake and about 2.2 million hectares of coastal salt marshes and mudflats. The area of wetland is equivalent to 2.7% of the land surface. China also has 2.7 million hectares of shallow sea water (less 5m in depth at low tide). Marshes and bogs are equivalent 1.3% of the land surface. Only three provinces (regions)—Qinghai, Xizang (Tibet) and Heilongjiang — have a larger total area of marsh and bog. According to the structure, type and development of wetland in different river basins, wetland can be classified nine main regions. The experiments indicate that the coefficient of the marsh to regulate flood is similar to that of lakes. Wetlands occupy 17.8% of the Sanjiang Plain area, the annual carbon contribution is 0.78 × 104t. Carbon released from marsh soil return into atmosphere is 3.95 × 106t/a. At present there is a sharp contradiction between population growth and natural resources shortage, causing wetland to be exerted with huge pressures and serious threats. Foundation item: Under the auspices of the Key B Item of the Chinese Academy of Sciences (KZ951-B1-201-02). Biography: LU Xian-guo (1957 —), male, a native of Changchun City, Jilin Provice, professor. His research interests include wetland process and environmental effect.  相似文献   

18.
本文从地貌、水系形式论述江汉盆地新构造的特点。指出江汉盆地为一继承性沉降盆地,同时新构造又具新生性。新构造运动的类型有差异升降运动、掀斜和拗折运动。江汉平原第四纪植物孢粉组合反映气候冷暧交替。鄂西山地发育了山谷冰川,平原区为湖河交错,受新构造运动影响,云梦泽逐渐解体。  相似文献   

19.
Wetland economic valuation approaches and prospects in China   总被引:1,自引:0,他引:1  
Ecosystem services valuation seeks to increase the social relevance of ecosystem characteristics, the underlying biological mechanisms that support services, by making the contribution of ecosystems to human well-being explicit. Economic valuation can help management by clarifying the full range of benefits and costs of proposed management actions. In the past two decades, economic valuation of wetland ecosystem services has become one of the most significant scientific priorities for wetland protection. In this paper, we provide an overview of ecosystem services, and summarize the main interdisciplinary approaches to measure and value wetland ecosystem services. We identified four main methodological gaps preventing progress on wetland valuation of ecosystem services in China, which are: 1) confusion on terminology like intermediate and final ecosystem services, 2) lack of ecological production functions to link ecosystem characteristics to final ecosystem services, 3) static valuation making it difficult to evaluate the trade-offs and synergies among ecosystem services, and 4) lack of clear guidance on relating ecological compensation programs to conservation targets. Overcoming these gaps is important to inform wetland compensation mechanisms and conservation policies. We propose future research on wetland ecosystem services in China should be focused on: 1) defining final ecosystem services based on beneficiary preferences and underlying biophysical mechanisms, 2) establishing wetland monitoring programs at specific sites to collect data on final ecosystem service indicators and ecosystem characteristic metrics to create ecological production functions for economic valuation and rescaling techniques, and 3) incorporating wetland ecosystem service values into decision-making processes to inform wetland management.  相似文献   

20.
应用微动台阵法在江汉平原和长江大堤开展应用实验。结果表明,空间自相关法比频率-波数法结果更为稳定;通过变换台阵的尺寸可以探测浅至数米深至数百米的地下结构信息;利用台阵在空间上的平移观测可获取地下二维及三维的结构信息。  相似文献   

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